The present invention relates to roll headers, and more particularly to roll header platens.
In the paper manufacturing industry, paper is prepared in long ribbons which are wound or spooled to form cylindrical rolls. Typically, the rolls of paper are wrapped with a protective wrapping, or roll wrapper, in the form of a strip of paper wrapped about the cylindrical surface of the roll and protruding at least several inches beyond each end of the roll. The protruding ends of the wrapper are flattened against the ends of the roll by forming crimps or folds about the peripheral edges of the wrapper. Heavy paper discs or "heads" are usually adhered to the ends of the wrapped rolls to seal the ends thereof.
Often, a two-piece head is used at each end of the roll. An inner head is inserted within the crimped end of the roll wrapper, and an outer head overlies the crimped wrapper edge. The outer head includes a heat activatable adhesive, such as polypropylene, on its inside surface. A heated platen then engages the outer head to force the head against the roll and to tackify the adhesive, sealing the head to the roll. The polypropylene on the inside surface of the outer head acts both as an adhesive and as a vapor barrier. However, this method of heading a paper roll is relatively expensive inasmuch as two heads are required at each end of the roll (i.e., one inside the crimped wrapper and one outside the crimped wrapper). If the inside head is omitted, the outside head adheres to the rolled paper exposed at the roll end inwardly of the crimped roll wrapper.